Screwdriver with integral magnetic screw starter

ABSTRACT

A screwdriver having an integral magnetic screw starter to accommodate the same size and type of screws as the cooperative screwdriver head. The driver head of the magnetic screw starter matches the associated driver head of the screwdriver size and type. The magnetic screw starter comprises a high magnetic strength permanent magnet for securely holding the screw to be started. In one embodiment the magnetic screw starter is constructed with a magnetic starterhead having an area comparable in size to the screw to be started, and a slightly raised portion for engaging the slot in the head of the screw to be started. The magnetic screw starter is recessed in the screwdriver handle for protection and for limiting the size of screw which it can accommodate. The disclosed construction provides a magnetic screw starter for securely holding selected size and types of magnetizable fasteners. The teaching of this invention can be applied to screwdrivers having various type of heads such as clutch, Phillips, socket, hex, or the like. The recess in the screwdriver handle and the diameter of the permanent magnet can provide additional help for supporting the screw to be started.

United States Patent [1 1 Dobrosielski 1 SCREWDRIVER WITH INTEGRALMAGNETIC SCREW STARTER [76] Inventor: Stephen Stanley Dobrosielski, 429E.

End Ave., Beaver, Pa. 15009 [22] Filed: Apr. 29, 1974 [21] Appl. No.:464,943

Primary ExaminerA1 Lawrence Smith Assistant Examiner-Marc R. DavidsonAttorney, Agent, or FirmHoward G. Massung 57] ABSTRACT A screwdriverhaving an integral magnetic screw [H1 3,884,282 1 May 20, 1975 starterto accommodate the same size and type of screws as the cooperativescrewdriver head. The driver head of the magnetic screw starter matchesthe associated driver head of the screwdriver size and type. Themagnetic screw starter comprises a high magnetic strength permanentmagnet for securely holding the screw to be started. In one embodimentthe magnetic screw starter is constructed with a magnetic starterheadhaving an area comparable in size to the screw to be started, and aslightly raised portion for engaging the slot in the head of the screwto be started. The magnetic screw starter is recessed in the screwdriverhandle for protection and for limiting the size of screw which it canaccommodate. The disclosed construction provides a magnetic screwstarter for securely holding selected size and types of magnetizablefasteners. The teaching of this invention can be applied to screwdrivershaving various type of heads such as clutch, Phillips, socket, hex, orthe like. The recess in the screwdriver handle and the diameter of thepermanent magnet can provide additional help for supporting the screw tobe started.

7 Claims, 6 Drawing Figures SCREWDRIVER WITH INTEGRAL MAGNETIC SCREWSTARTER BACKGROUND OF THE INVENTION This invention relates toscrewdrivers and more particularly to a screwdriver having an integralmagnetic screw starter.

Prior art mechanical screw starters are difficult and expensive tomanufacture and cannot be used on all varieties of screws. such as, ascrew having a nonremovable type head which prevents the screw frombeing backed out after insertion. Prior art screwdrivers having amagnetized primary driver head tend to have a low holding force and havedifficulty in holding long screws or screws having special heads. suchas the nonremovable variety The steels required for a general purposescrewdriver head generally do not have the necessary properties for ahigh strength permanent magnet. A high quality permanent magnet can bemade from a hard. high carbon steel. but this is too brittle and notacceptable for a general purpose screwdriver head.

SUMMARY OF THE INVENTION A screwdriver having an integral magnetic screwstarter which can accommodate selected varieties and sizes of fasternersis provided. The screw starter is constructed to he used in cooperationwith the primary screwdriver head for securing the selected fastners toa workpiece.

The screwdriver. with integral magnetic screw starter. comprises ashank. with a primary driver formed at the free end thereof, extendingfrom one end of an elongated handle. and a magnetic screw starterattached to the other end of the handle. The screw starter is formedfrom a high magnetic strength permanent magnet, The screw starter has adriver head constructed to match the primary driver in the size and typeof screw accommodated. The magnetic screw starter can be recessed in thehandle for protection against mechanical damage and to limit the size offastener to which it can be applied. The opening into which the screwstarter is recessed can also be used for providing support for somescrews. The driver of the magnetic screw starter projects only slightlyabove the magnetic body. from which it is formed. providing a strongholding force; since the body of the magnet can directly contact a largeportion of the head of the screw to be retained.

The disclosed screwdriver having an integral magnetic screw starter issimple and inexpensive to manufacture. It can be built for all sizes andtypes of screwdrivers. with each magnetic screw starter head matchingthe associated primary screwdriver head. The body of the starter incontact with the screw head provides a strong holding force and caneasily hold long screws having heads of the non-removable variety, whichcannot be held securely by prior art magnetic screwdrivers.

It is an object of this invention to provide a magnetic screw starter.having superior magnetic holding force. recessed in an opening in ahandle which provides mechanical protection and limits the size and typeof screws which can be accommodated.

It is a further object of this invention to provide a screwdriver havinga magnetic screw starter formed integral therewith opposite the primaryscrewdriver head. constructed to accommodate the same size and type ofscrew as the primary screwdriver head.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding oftheinvention reference may be had to the preferred embodiment exemplary ofthe invention shown in the accompanying drawings in which:

FIG. 1 is a perspective view of a screwdriver utilizing the teaching ofthe present invention;

FIG. 2 is a side sectional view of a screwdriver utilizing the teachingof the present invention;

FIG. 3 is a side view of a portion of a screwdriver for Phillips headscrews utilizing the teaching of the present invention;

FIG. 4 is similar to FIG. 3, but for a hex head fastener;

FIG. 5 is similar to FIG. 3, but, for a socket head fastener; and

FIG. 6 is similar to FIG. 3, but for a clutch head fastener.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawingsand FIGS. 1 and 2 in particular there is shown a screwdriver I0utilizing the teaching of the present invention. The screwdriver 10 hasan integral magnetic screw starter 12 which can accommodate the samesize and type of fastener as the primary driver head 14. As in aconventional screwdriver the driver head I4 is located on the free endof a shank 16 extending from one end of an elongated handle 18. ShankI6, which is normally formed from a steel material having a relativelyhigh structural strength, is securely connected to handle I8 and canprovide torque to fasteners engaged by driver head 14 as handle 18 isrotated.

A magnetic screw starter 12 is disposed in the end of the handle 18opposite the connection to shank I6. Screw starter 12 is formed from amaterial having a high magnetic strength for securely holding selectedfasteners. The screw starter 12 can be formed from a hard high carbonsteel which can make a good, high strength permanent magnet. but whichis too brittle and not acceptable for a general purpose screwdriverhead. The magnetic screw starter 12 is disposed in an opening 20 formedin handle 18. Screw starter I2 is securely connected to handle 18 toprevent relative movement of the starter 12 with respect to handle 18.

The magnetic screw starter 12 comprises a permanent magnet body portion21 having a mechanical driver 22 formed on its exposed end, to providethe required torque when handle 18 is rotated to start a screw 28. Thedriver 22 formed on the magnetic starter I2 is constructed to handle thesame size and type of fasteners as the associated primary driver head14. The primary driver head I4 is made to work with limited sizes ofscrews and the magnetic starter 12 is made to be used in cooperationwith the primary screwdriver head 14 for starting the same size and typeof screws or fasteners with which the primary driver head 14 can work.

The magnetic screw starter 12 can be recessed in handle 18. as bestshown in FIG. 2. Handle 18 is preferably formed from a non metallicresin or plastic mate rial. With the magnetic starter 12 recessed inopening 20, the size and shape of opening 20 can determine the varietyof fasteners which the magnetic screw starter 12 can accommodate.Opening 20 can have a counterbore 24, formed at the outer open end, ableto accommodate fasteners having a head shape different than the shape ofthe starter 12. That is. the size and shape of the counter bore 24 canbe used to determine what fasteners can be held by the magnet screwstarter 12. As shown in FIG. 2, for certain size fasteners the counterbore 24 in contact with the screw head 26 can provide additionalsupport. This is. the larger fasteners which can be accommodated by therecessed magnetic screw starter 12 will contact the sides of counterbore 24 and thus prevent the free end of fastener 28 from rotating ormoving around the holding points of starter 12. This helps assure thatmagnetic screw starter 12 will se curely hold fastener 28.

To further assure adequate holding power for the magnetic screw starter12 the body portion 2] is constructed to have a relatively largecross-sectional area. The large cross-sectional area or diameter of bodyportion 21 of magnetic starter 12 provides a flat planar surface 27 thatincreases the pulling or holding force at a much improved rate over thatwhich can be provided by an ordinary screwdriver having a magnetizeddriver head.

The height of driver 22 is made relatively small so that the fastenerhead 26 can directly contact the flat planar surface 27 of magneticstarter 12. This provides a substantially greater holding force than canbe achieved when the magnetic contact is made primarily between thedriver 22 and the screw slot.

Since screw starters are generally required in tight work areas or whereonly one hand can be used it is very desirable that the screw to bestarted be held securely and not twist or wobble as the screwdriver ismoved. The screw to be started should be securely held in a relativelyfixed position with respect to the screwdriver handle 18 and should notshift as the orientation of the screwdriver is changed. Prior artmagnetic screwdrivers have had problems in securely hold screws undervarious conditions. The disclosed screwdriver 10 has an integral screwstarter 12 which can hold many types of screws securely. The screw head26 in contact with counter bore 24, and the top 27 of starter 12 incontact with screw head 26 provide for relatively rigid holding of screw28 regardless of screwdriver 10 movement or orientation.

Having the magnetic starter l2 recessed in handle 18, with no portionprojecting beyond the end of handle 18 also serves to protect thestarter 12 from physical damage due to screwdriver l mishandling. Thisallows a relatively brittle material. which has good magnetic propertiesbut poor physical strength. to be used for forming magnetic starter [2.Having the magnetic starter l2 recessed also assures that screwdrivercan accommodate and will be used only to start screws for which it isdesigned. As stated above. the counter bore 24 can also help to supportproperly sized screws.

The advantages of the disclosed screwdriver 10 are particularly evidentwhen considered for use on screws or bolts which are meant to benon-removable. Nonremovable screws have a head with only a partial slotformed therethrough. Half of each side wall which would define the slotare removed; thus, turning the screw, by inserting a driver in thepartial slot and rotating, is possible in one direction only. That is. anonremovable screw can be inserted by rotating a driver inserted in thescrew slot. but the screw cannot be removed since the portion of theslot against which the driver must act for backing out rotation isremoved.

These non-removable screws are particularly difficult for most screwstarters to handle. Mechanical starters which require a complete slotwith facing side walls cannot be used. An ordinary screwdriver with amagnetized driver head is not. in effect. securely holding nonremovablescrews since most of the magnetic holding force is concentrated in thepartial slot. The disclosed magnetic screw starter 12 in which the screwhead contacts a larger portion of the holding magnet can effectivelyhold screws with non-removable heads. The disclosed screw starter 12provides a larger magnet in contact with the screw head 28 than ispresent in prior art magnetic screw holders. The counter bore 24 alsohelps support selected non-removable screws. and recessing the magneticstarter 12 in handle 18 allows a stronger but more fragile magnet to beutilized.

Referring now to FIGS. 3 through 6 there are shown various embodimentsof the present invention. As in the embodiment shown in FIGS. 1 and 2,the magnetic starter head of each screwdriver is constructed only tocooperate with and handle the same size and type of fastener as theprimary driver head is designed to handle. FIG. 3 shows a screwdriverwith a magnetic screw starter 42 constructed to handle Phillips headscrews. FIG. 4 shows a screwdriver utilizing the teaching of thisinvention to be used for handling hex head fasteners. A magnetic screwstarter 43 for hex head fasteners is provided. FIG. 5 shows ascrewdriver with a magnetic screw starter 44 for holding socket headfasteners. FIG. 6 shows a screwdriver with a magnetic screw starter 46constructed, for use with the clutch head fasteners. The operation andadvantages of the screwdrivers shown in FIGS. 3 through 6 are similar tothose described above for the embodiment shown in FlGS. l and 2. The magnetic screw starters as shown in FIGS. 3 through 5, are recessed in thehandle 18 for mechanical protection, have a relatively large magneticbody portion for strong holding force, and the shape of the counter boreand magnetic driver head 42, 43, 44, or 46 are formed to onlyaccommodate the same size and type of fastener as the associated primarydriver head.

Since numerous changes may be made in the above described apparatusdifferent embodiments of the invention may be made without departingfrom the spirit and scope thereof, it is therefore intended that all thematter contained in the foregoing description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

What is claimed is:

l. A screwdriver with integral, magnetic screw starter comprising:

an elongated handle;

a shank formed of a first material attached to and extending from oneend of said elongated handle;

a first driver head formed at the free end of said shank;

an elongated magnetic screw starter, longitudinally aligned with saidshank, formed of a second material having superior magnetizableproperties and attached to the other end of said elongated handleopposite said shank; and,

a second driver head formed at the exposed end of said magnetic screwstarter and being constructed for use in cooperation with said firstdriver by only accommodating the same size and type of screw as saidfirst driver.

2. A screwdriver as claimed in claim 1, wherein:

said elongated handle is formed from a non-metallic material and has anopening formed therein; and, said magnetic screw starter comprises anelongated unitary body portion recessed and permanently secured in theopening formed in said elongated handle. 3. A screwdriver as claimed inclaim 2. wherein: said second driver head is formed at the exposed endof said elongated body portion of said magnetic screw starter and isrecessed and does not extend beyond the end of said elongated handle;and. said second driver head extends from said magnetic screw starter alength less than the depth of the recess in the screw head of the screwto be started. 4. A screwdriver as claimed in claim 3, wherein: saidelongated handle has an opening formed therein in which said magenticscrew starter is recessed, of a size and shape to only accommodate thefasteners which said first driver head is designed to handle. 5. Ascrewdriver a claimed in claim 3, wherein: said elongated magnetic screwstarter is cylindrical shaped with a diameter equal to the width of saidsecond driver 6. A screwdriver as claimed in claim 1, wherein: saidmagnetic screw starter comprises a unitary magnetic member;

said second driver extends from a flat planar surface formed at theexposed end of said magnetic screw starter; and

said second driver being ofa small length so that the head of the screwto be started can contact the flat planar surface which is magnetized.

7. A screwdriver as claimed in claim 6, wherein:

said magnetic screw starter comprises a unitary magnetic member which isrecessed and permanently secured in said elongated handle;

a counter bore is formed around the exposed end of said magnetic screwstarter to limit the size and type of screw head which can beaccommodated by said magnetic screw starter to conform to the size andtype of screw which said first driver is formed to handle;

said counter bore is constructed to contact the head of the screw to beretained when the screw to be started is held by said magnetic screwstarter in contact with said flat planar surface of said magnetic screwstarter; and,

said handle is formed from a nonmetallic material

1. A screwdriver with integral, magnetic screw starter comprising: anelongated handle; a shank formed of a first material attached to andextending from one end of said elongated handle; a first driver headformed at the free end of said shank; an elongated magnetic screwstarter, longitudinally aligned with said shank, formed of a secondmaterial having superior magnetizable properties and attached to theother end of said elongated handle opposite said shank; and, a seconddriver head formed at the exposed end of said magnetic screw starter andbeing constructed for use in cooperation with said first driver by onlyaccommodating the same size and type of screw as said first driver.
 2. Ascrewdriver as claimed in claim 1, wherein: said elongated handle isformed from a non-metallic material and has an opening formed therein;and, said magnetic screw starter comprises an elongated unitary bodyportion recessed and permanently secured in the opening formed in saidelongated handle.
 3. A screwdriver as claimed in claim 2, wherein: saidsecond driver head is formed at the exposed end of said elongated bodyportion of said magnetic screw starter and is recessed and does notextend beyond the end of said elongated handle; and, said second driverhead extends from said magnetic screw starter a length less than thedepth of the recess in the screw head of the screw to be started.
 4. Ascrewdriver as claimed in claim 3, wherein: said elongated handle has anopening formed therein in which said magentic screw starter is recessed,of a size and shape to only accommodate the fasteners which said firstdriver head is designed to handle.
 5. A screwdriver a claimed in claim3, wherein: said elongated magnetic screw starter is cylindrical shapedwith a diameter equal to the width of said second driver. Pg,12
 6. Ascrewdriver as claimed in claim 1, wherein: said magnetic screw startercomprises a unitary magnetic member; said second driver extends from aflat planar surface formed at the exposed end of said magnetic screwstarter; and said second driver being of a small length so that the headof the screw to be started can contact the flat planar surface which ismagnetized.
 7. A screwdriver as claimed in claim 6, wherein: saidmagnetic screw starter comprises a unitary magnetic member which isrecessed and permanently secured in said elongated handle; a counterbore is formed around the exposed end of said magnetic screw starter tolimit the size and type of screw head which can be accommodated by saidmagnetic screw starter to conform to the size and type of screw whichsaid first driver is formed to handle; said counter bore is constructedto contact the head of the screw to be retained when the screw to bestarted is held by said magnetic screw starter in contact with said flatplanar surface of said magnetic screw starter; and, said handle isformed from a nonmetallic material.